This invention relates to dynamoelectric machines, and in particular, to a device for precisely mounting a hall effect sensor on a stator assembly of an electric motor. While the invention is described with particular reference to such application, those skilled in the art will recognize the wider applicability of the inventive principles disclosed hereinafter.
As is well known in the art, hall effect sensors often are used in conjunction with the operation of brushless permanent magnet motors. Such motors typically include a stator assembly and a rotor assembly. Permanent magnets are mounted to the rotor assembly, and their passage across the hall effect sensor enables associated circuitry to determine the position of the rotor. Rotor position is used to control energization of the motor windings for proper motor operation. It has been common, in the past, to mount the hall effect assembly to the endshield or end bell of the motor. The motor endshields, in general, are used to house at least one bearing which supports a shaft and rotor. Proper location of the hall effect sensor both with respect to the stator and to the associated rotor magnets required that the endshield, or a device mounted to the end shield, be adjusted during the motor assembly process. Such adjustment is time consuming, and adds to product cost. More importantly, it is difficult to accurately locate the sensor when so mounted, with resultant degradation in motor operation.
One of the objects of this invention is to provide a low cost hall effect assembly for a dynamoelectric machine.
Another object of the invention is to provide a hall effect assembly for a dynamoelectric machine which precisely positions the hall effect sensors utilized in conjunction therewith.
Another object of this invention is provide a hall effect assembly which allows easy construction of the assembly itself.
It is another object of this invention to provide a hall effect assembly which positionally is self maintain with respect to an associated stator assembly.
Another object of this invention is to provide an enclosure for accommodating a plurality of hall effect sensors.